They'd fit if you got creative. You could always put pieces of them in someone else's box. :)

7 billion people in cramped boxes, some of them with limbs amputated and some of them with body parts in their box, with no ventilation, waste disposal or food supply. Sounds like a great xkcd what-if. That reminds me that you can fit 7 billion people on Rhode Island, but the geopolitical effects of that would be less than beneficial.